The development of a climate facade for a hot humid climate

1. Introduction For many new buildings in the United Arabic Emirates, in cities like Dubai and Abu Dhabi, the "green building concept" is the starting point of design. These buildings should have a modern and open character, integrated with Arabic cultural elements. One of the goals of the green building concept is a low energy consumption. Some de-sign starting points of energy reduction are: - cool as much as possible with water instead of air - reduce solar heat entering the façade - make use of daylight as much as possible At the moment several buildings with almost 90% glass façades are developed in the U.A.E.. This seems to create both problems of overheating and a high energy consump-tion. However, with the use of a climate façade, it is possible to compensate for these negative influences. 2. Methods Design and physical principles of conventional climate façades were analysed. Based on these analyses the climate façade concept was adapted to hot and humid climates. For instance, double glass on the outside should have a low g-value of at least approx. 0.3. By means of simulations in TRNSYS and CFD (Phoenics), predictions of temperatures were made. A mock-up room with a climate façade was built. Measurements of air flow, temperature, solar radiation and humidity gave a lot of information. Moreover, indicative measurements showed the effect of this type of façade equipped with reflect-ing blinds on visual comfort. One of the most important evaluation parameters is the technical performance of the façade; damage to the façade due to local high temperatures or quick changes in tem-peratures should be prevented. In order to predict the energy qualities, the climate façade is compared with other fa-çades like a conventional façade with solar protected (reflecting) glass, a natural venti-lated second skin façade and a façade with solar shading elements on the outside. 3. Results The results show a good relation between simulations and measurements of the thermal performance of the façade. The measurements give also some information about both the energetic and visual performance. With this information the performance of other types of climate façade's can be predicted more accurately in the future. 4. Conclusion and recommendations This research of the climate façade shows the usefulness of design tools and shows inspiring new ideas for open transparent buildings in hot humid climates. Recommenda-tions are given about measurements in hot humid climates, the performance of mock-up rooms in these areas and control systems.